whenever 可以作连词conj用，意思是”每当”，“无论何时”,相当于no matter when。例如：
1.whenever we met with disabilities,they came to help us.=No matter when we met with disabilities,they came to help us.
2.we try to help whenever(it is) possible.=we try to help no matter when(it is )possible.
whenever还可以作副词用，用在疑问句中，表示惊奇，意思是“究竟什么时候”，例如：
3.whenever did I make such a promise?
